In recent years, display devices with a greater display area are highly anticipated because of higher performance and advanced design in the technical field of mobile data communication devices such as mobile phone and personal digital assistant (PDA). For example, display devices including a thinner bezel structure are proposed.
Conventionally, there is a well-known structure in which a driver is mounted in the periphery of the display area on the substrate including electrodes. In display devices using such a structure of the driver, input signals and voltages are supplied to the driver through a line substrate such as a flexible printed circuit (FPC). On the other hand, instead of such a flexible printed circuit, there has been proposed a method to form an electrical connection between lines formed on the lower surface side of an array substrate and the driver formed on the upper surface side of the array substrate through a laser-formed contact hole passing through the array substrate.